A 35-month-old girl with leukocoria was clinically diagnosed with unilateral sporadic retinoblastoma. Macroscopic examination of her enucleated eye disclosed a white retinal tumor that appeared to be a retinoblastoma. Histopathologic examination, however, revealed that the tumor was composed of poorly differentiated neuroblastic cells, larger spindle-shaped cells, and anaplastic epithelioid cells, which is inconsistent with retinoblastoma. Immunohistochemical testing disclosed that the tumor cells were immunoreactive for melanoma-specific antigen HMB-45, while electron microscopy showed premelanosomes in the tumor cells, both of which are consistent with melanogenesis. To our knowledge, such an ocular tumor has not been reported previously.
Freitag SK, Eagle RC, Shields JA, Duker JS, Font RL. Melanogenic Neuroectodermal Tumor of the Retina (Primary Malignant Melanoma of the Retina). Arch Ophthalmol. 1997;115(12):1581-1584. doi:10.1001/archopht.1997.01100160751015